There are no surprises here. The handwriting has been on the wall for this for a long, long time. AA simply held off because it had fish to fry, e.g. dealing with the US acquisition of the old AA.
Why no surprises? AA faces the same competitive landscape as UA and DL. Certainly it might analyze the data differently from DL and UA, but the facts are the facts.
Improved economy, less capacity, less competition. Perhaps most important, increased reliance on massive corporate contracts where FFP is meaningless and the people who matter are conferred EXP by the corporate deal. All of that comes down to less of a need to give stuff away and a greater focus on HVC's, e.g. spend.